With about 10:40 left in the fourth quarter, Klay missed a left-wing 3-pointer and landed awkwardly.
Thompson exited Golden State's 109-104 win on Sunday midway through the fourth quarter.
Looney has played a nice role for the two-time defending NBA Champions, giving them an average of just over 20 minutes per game. He provides excellent depth at the center position for the Warriors.
The Toronto Raptors feel good mentally, and they are certainly in better shape physically than the Golden State Warriors. He will be out indefinitely because of a non-displaced cartilage fracture on the right side of his ribcage that he sustained in Game 2.More news: Trump expects tariffs on Mexico to go in effect
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Golden State is a 4.5-point favorite with the total at 213.5 in the latest Warriors vs. Raptors odds.
Kerr said postgame, "Klay said he'll be fine, but Klay could be half-dead and he would say he would be fine". "We'll see. He pulled his hamstring".
Everyone gets a free taco from Taco Bell thanks to the Warriors' Game 2 victory over Toronto. And it has been particularly red-hot on its A-rated NBA money line picks, entering the 2019 NBA Finals on a strong 85-61 run.
Thompson was critical to Golden State's win Sunday, scoring the Warriors' first nine points en route to a team-high 25.